•Cascading
•Rotating
•Concurrent
Each of these types describes a different set of relationships between nodes in the cluster, and a different set of behaviors upon nodes entering and leaving the cluster.
Cascading Resource Groups: All nodes in a cascading resource group are assigned priorities for that resource group. These nodes are said to be part of that group's resource chain. In a cascading resource group, the set of resources cascades up or down to the highest priority node active in the cluster. When a node that is serving the resources fails, the surviving node with the highest priority takes over the resources.
A parameter called Inactive Takeover decides which node takes the cascading resources when the nodes join the cluster for the first time. If this parameter is set to true, the first node in a group's resource chain to join the cluster acquires all the resources in the resource group. As successive nodes join the resource group, the resources cascade up to any node with a higher priority that joins the cluster. If this parameter is set to false, the first node in a group's resource chain to join the cluster acquires all the resources in the resource group only if it is the node with the highest priority for that group. If the first node to join does not acquire the resource group, the second node in the group's resource chain to join acquires the resource group, if it has a higher priority than the node already active. As successive nodes join, the resource group cascades to the active node with the highest priority for the group. The default is false.
Member nodes of a cascading resource chain always release a resource group to a reintegrating node with a higher priority.
Rotating Resource Groups: A rotating resource group is associated with a group of nodes, rather than a particular node. A node can be in possession of a maximum of one rotating resource group per network.
As participating nodes join the cluster for the first time, they acquire the first available rotating resource group per network until all the groups are acquired. The remaining nodes maintain a standby role.
When a node holding a rotating resource group leaves the cluster, either because of a failure or gracefully while specifying the takeover option, the node with the highest priority and available connectivity takes over. Upon
